Remote controlled actuator assemblies are currently available; some are used for operations like cutting operations in, for example, the medical field or the mechanical processing field. Any of those remote controlled actuator assemblies controls by remote control an operating tool such as a machine tool or a holding tool that is fitted to a distal end of an elongated guide section of a linear or curved configuration. In the following description, conventional art and problems will be discussed with reference to remote controlled actuator assemblies in the medical field used for osteal treatment.
In orthopedics, the artificial joint replacement is well known, in which a joint, of which bone has been abraded by due to bone deterioration, is replaced with an artificial joint. The joint replacement surgery requires a living bone of a patient to be processed to enable an artificial joint to be implanted. In order to enhance the strength of postoperative adhesion between the living bone and the artificial joint, such processing is required to be performed precisely and accurately in conformity to the shape of the artificial joint.
By way of example, during the hip joint replacement surgery, a thigh bone is opened to secure access of an artificial joint into the femoral marrow cavity. In order to secure a strength of contact between the artificial joint and the bone, surfaces of contact of the artificial joint and the bore must be large and so the opening for insertion of the artificial joint is processed to represent an elongated shape extending deep into the bone. For such a processing, a remote controlled actuator assembly is used which is capable of rotating by remote control an operating tool fitted to a tip end of an elongated guide section. The surgical operation for artificial joint replacement generally accompanies skin incision and muscular scission. In other words, the human body must be invaded. In order to minimize the postoperative trace, it is quite often desirable that the elongated guide section referred to above is not necessarily straight, but is moderately curved.
To meet this desire, the following technique has hitherto been suggested. For example, the Patent Document 1 listed below discloses the guide section having its intermediate portion curved twice to displace an axial position of the distal end of the pipe relative to the longitudinal axis of the proximal end of the same pipe. To make the axial position of the distal end of the guide section displace relative to the longitudinal axis of the proximal end of the same guide section is also known from other publications. Also, the Patent Document 2 listed below discloses the guide section rotated by 180°.